Electric jet-forming apparatus



lC -ll 53. q: 36 G a 6 1 4 United States Patent ELECTRIC JET-FORIVIINGAPPARATUS George E. Mallinckrodt, 20 Kingsbury Place, St. Louis 12, Mo.

This invention relates to electric apparatus for the production of anatomic jet adapted for gas evacuation, spraying, reactive propulsion andany other processes which may be actuated by such a jet, such aslow-energy nuclear reactions.

Among the several objects of the invention may be noted the provision ofelectric jet-forming apparatus adapted to maintain a rapid flow in jetform of atomic particles; and the provision of a simple form of suchapparatus wherein the jet-forming material is accelerated as a stream ofpositively charged atoms and becomes a high-speed jet of atoms adaptedfor reactive propulsion, pumping of gases, nuclear reactions spraying ofparticles such as metal, and the like. Other objects and features willbe in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the elements and combinations ofelements, features of construction, and arrangements of parts which willbe exemplified in the structures hereinafter described, and the scope ofwhich will be indicated in the following claims.

In the accompanying drawing, the single figure is a diagrammatic axialsection of apparatus embodying my invention.

Referring now to the drawing, numeral 1 indicates an electricallyinsulating base on which are located spaced conductive terminals 3 and5. These support conductive electrodes 7 and 9, respectively. Theelectrodes 7 and 9 are composed of the material or materials which areto become a desirable component of the jet to be produced, as forexample a metal if the jet is to be used for metal spraying, an exampleof which would be copper. The term metal as used herein includes alloys.For reactive propulsion purposes, the heavier metals may be preferable.Or the electrodes 7 and 9 may be composed of nonmetallic materials suchas carbon in propulsive applications of those wherein gas evacuation isthe object in view.

Each electrode may be in the form of a hollow cylinder, which forexample may be 2 feet long, 3 inches in diameter (shown at 11), andhaving a Ila-inch hole 13 therethrough. Electrode 7 has a tapered inletopening 15, and electrode 9 has a tapered outlet opening 17. Theelectrodes 7 and 9 are spaced apart a distance 19 which may beapproximately equal to the diameters indicated at 11. A finned coolingjacket 21 surrounds the electrodes and the space between them, andcarries a liquid coolant, such as water or sodium. The coolant may flowin at an entrance 23 and leave at an exit 25 for circulation through asuitable heat exchanger.

The space between the electrodes 7 and 9 is surrounded by one or moreannular field coils. For example, three of such coils 27, 29 and 31 areshown, having suitable exciting circuits 33, 35 and 37 for applyingappropriate D.C. voltages to the coils. Each coil is so wound and eachvoltage is so applied that together the coils form aiding toroidalmagnetic fields. The sectional form of the sum is suggested by thedotted circles 39. The cir- 2,960,614 Patented Nov. 15, 1960 clessuggest one axial section through a toroidal magnetic field 41. It willbe understood that the form 41 is idealized and that it is subject todistortions, without, however, changing its essentially toroidal form.Thus the dotted lines 39 and 41 are skeleton representations of theactually more extensive toroidal field.

At 43 is shown a connection with the space 45 between the electrodes 7and 9. This connection is provided with a valve 47. At 49 is shown aninlet chamber and at 51 a connection therewith in which is a valve 53. Acommon passage 54 to both valves 47 and 53 is for making a suitableconnection with any compartment to be evacuated. The chamber 49 has alarge atmospheric inlet opening 55 opposite the inlet opening 15 of theelectrode 7. This opening 55 may be closed when desired by means of acontrol gate 57. Numeral 59 designates a DC. supply circuit connectedacross the terminals 3 and 5. This circuit for all applications suppliesa relatively large amperage at a substantial voltage, for example, 2,000to 5,000 amperes at to 250 volts. It is connected to charge 7 positivelyand 9 negatively. Upon supplying such a voltage and large current, anygas in space 45 is copiously ionized .when an arc is struck betweenelectrodes 7 and 9. The are makes the electrodes incandescent andvaporizes material from electrode 7. This material becomes atomized andionized. Since 9 is negative, it supplies negative charges which attractand neutralize atleast a majority of the ionized atoms or groups ofatoms (as the case may be) of materials in the are reaching 9.

Assuming that the coils 27, 29, 31 are excited to produce the toroidalfield 39, 41 as indicated, the flow of ions along the arc is subject toa magnetically constrictive spiraling action within the toroidalmagnetic flux field 41. The action is as follows, assuming that theelectrodes 7 and 9 are composed of copper, that the gate 57 is open, andthat the valves 47 and 53 are shut:

Atoms of gaseous materials (air, for example) and atoms of material fromelectrode 7 which enter the are all carry positive charges and, as abovestated, are therefor attracted to the negatively charged electrode 9. Itis the charged condition of the atoms or groups of them that is referredto herein as ionization. A tubular magnetic field is generated aroundthe flow of current represented by the moving positive charges, assuggested by the dotted lines 61. Its circular lines of force combinevectorially with the lines of force of the toroidal field 41 spirally toguide the flow of ions in the space 45 between electrodes 7 and 9 towardand along the center line 63. The spiraling action is toward and alongthe axis 63 of the toroidal magnetic field 39, said axis passing throughthe arc and the tubes 7 and 9. Thus the charged atoms tend to escapefrom 7 to 9 through a small central core of the space 45. In doing so,they accelerate and enter the passage 13 in electrode 9. The highestvelocities of these atoms are those segregated nearest the axis orcenter line 63. In passing through electrode 9, a majority of theirpositive charges are neutralized by the negative charges escaping fromthe hot electrode 9. Consequently at least some atoms become neutral andmove with a considerable kinetic energy, which causes them to becomeejected as a jet from the outlet 17 of electrode 9. The initialaccelerating force on the particles is produced by the potentialdifference between the electrodes 7 and 9. However, the velocity of thestream of particles ejected from electrode 9 is higher than if thisaccelerating force were applied to the particles without the additionalacceleration caused by the spiraling action toward and along axis 63,accomplished by the interaction of the magnetic fields 39 and 61. Thisspiraling action also has the effect of ordering the particle movementsalong the axis, so that those moving closer to the axis are not subjectto the large amount of resistance caused by random particle movements aswould be had if the spiraling function were not present. In other words,by means of the invention the amount of accelerating force available,due to the voltage drop selected between the tubes 7 and 9, is moreefficiently converted into kinetic energy 'associated with the higherparticle velocities ejected. Since the electrode 7 is composed ofcopper, the copper atoms issuing from the electrode 9 may be used formetal spraying onto any suitable interposed surface. In sprayingapplications of the invention, the jet of atoms of gas ejected from theoutlet 17 are not of practical significance. Obviously, if it isintended to form a metal spray of another metal or alloy, the electrode7 is made of the appropriate material for the purpose. It will beapparent that in time a sufiicient amount of material will be lost fromthe electrode 7 to require its replacement.

The kinetic energy of ejection is considerable, particularly that partof the flow along and close to the center lines of the holes in theelectrodes 7 and 9. Velocities are progressively less as the walls inthe holes of the electrodes are approached, which minimizes energy lossdue to lateral eddy currents.

If it is desired to employ the apparatus as a reaction motor, the base 1may be attached to the element to be moved, reaction due to accelerationof the particles being applied to the moving system through theelectrodes 7, 9 and the supports 3, 5. It will be understood that insuch applications, efliciency is increased with increasing speed of thedevice being moved. This application is therefore primarily forhigh-speed apparatus, which does not require a high starting force ortorque.

Another application of the apparatus is as a gas pump to effectevacuation of gaseous materials. For this purpose the gate 57 is closed.Then valve 53 may be opened, connection being made through 51 and 54with any compartment to be evacuated. The gas may be any one such asair, hydrogen, nitrogen, et cetera. Since discharge of the material fromthe outlet 17 includes the gas atoms, the chamber attached to theconnection 51 becomes evacuated. An alternative evacuation method is toclose gate 57 and valve 53 while opening valve 47, connection'being thenmade with the chamber to be evacuated. Or gate 57 may be closed and bothvalves 47 and 53 opened. As a gas pump, the device is useful down to apressure range on the order of 10" mm. mercury. Below such a pressurethe arc cannot be sustained.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawing shall be interpreted as illustrative and not in a limitingsense.

I claim:

1. Electric jet-forming apparatus comprising a pair of spacedelectrodes, a circuit connected to the electrodes adapted to maintainthem positive and negative respectively and maintaining an ionized arebetween them, whereby ions flow from the positive toward the negativeelectrode, the negative electrode supplying electrons neutralizing atleast some of the ions which approach it, the ion flow establishing afirst magnetic field surrounding itself, and means adapted to establisha toroidal second magnetic field having an axis and coacting with saidfirst magnetic field to spiral said ions toward and along said axis in adirection from the positive to the negative electrode, whereby a jet ofatoms is produced which accelerates from the positive electrode spirallyinward toward the negative electrode.

2. Electric jet-forming apparatus comprising a pair of spacedelectrodes, a circuit connected to the electrodes adapted to maintainthem positive and negative respectively and maintaining an ionized arebetween them, whereby ions flow from the positive toward the negativeelectrode, the negative electrode having wall portions forming a spacesurrounded thereby in which electrons are supplied for neutralizing atleast some of the ions which move into the space, the ion flowestablishing a first magnetic field surrounding itself, and meansadapted to establish a toroidal second magnetic field having an axisextending through said space and coacting with said first magnetic fieldadapted to spiral said ions toward and along said axis and into saidspace, whereby the ions are accelerated and neutralized to form a jet ofneutral atoms moving into said space.

3. Electric jetforming apparatus made according to claim 2, including anenclosure surrounding said are, and means establishing a connectionbetween said enclosure and a supply of material for entrainment with theions moving toward said space.

4. Electric jet-forming apparatus comprising a pair of spacedelectrodes, a circuit connected to the electrodes adapted to maintainthem positive and negative respectively and maintaining an ionized arebetween them, whereby ions flow from the positive toward the negativeelectrode, the negative electrode having a hole therethrough in whichelectrons are supplied for neutralizing the ions, the ion flowestablishing a first magnetic field surrounding itself, and meansadapted to establish a toroidal second magnetic field having an axisextending through said hole and coacting with said first magnetic fieldadapted to spiral said ions toward and along said axis and through saidhole, .whereby an accelerated jet of neutral atoms is produced movingout of said hole.

5. Electric jet-forming apparatus comprising substantially axiallyspaced hollow tubular electrodes with adjacent ends of their hollowportions opposite one another, an electric circuit connected across saidelectrodes adapted to establish a potential and an ionized are betweenthem wherein ions fiow from the electrode of positive potential to theelectrode of negative potential, and means for establishing a toroidalmagnetic flux field surrounding said arc in the region of the spacingbetween the electrodes, whereby the other end of the tubular electrodeof positive potential constitutes a particle inlet and the other end ofthe tubular electrode of negative potential constitutes a particleoutlet.

6. Electric jet-forming apparatus made according to I claim 5, includingmeans adapted to supply said inlet with material for entrainment withsaid ion flow.

7. An electric jet-forming apparatus made according to claim 6,including an enclosure surrounding said arc, and means establishing aconnection between said enclosure and material for entrainment with saidion How.

8. Electric jet-forming apparatus comprising tubular electrodes whichare axially spaced, an electric circuit connected across said electrodesadapted to establish an ionized are between them and traversing saidspace, and means for establishing a toroidal fiux field surrounding saidspace and having an axis passing through the electrodes and through thearc.

9. Electric jet-forming apparatus comprising spaced first and secondelectrodes, an electric circuit connected across said electrodes adaptedto make the first one positive relative to the second one and toestablish between them an arc of ionized particles moving from the firstto the second electrode, said second electrode being tubular and adaptedto receive said ionized particles therem to become neutralized andejected therefrom means adapted to establish a toroidal flux fieldaround said arc, said field having an axis extending through the arc anddirected into said tubular second electrode, and a connection with saidspace adapted to supply gas thereto.

10. Electric jet-forming apparatus made according to claim 9, whereinsaid connection is made through said first electrode.

11. Electric jet-forming apparatus comprising spaced first and secondelectrodes, an electric circuit connected across said electrodes adaptedto make the first one positive relative to the second and to establishbetween them an arc of ionized particles moving from the first to thesecond electrode, means for establishing a toroidal magnetic flux fieldaround and in the arc and having an axis extending therethrough: saidsecond electrode being hollow and adapted to receive ionized particlesmoving along said axis to become neutralized and to eject saidparticles, and a connection with said space adapted to supply gasthereto.

12. Electric jet-forming apparatus comprising spaced first and secondelectrodes, a source of DC. power connected across said electrodesadapted to make the first one positive relative to the second and toestablish between them a high-current-density and low-resistance arc ofionized particles accelerating-from the first to the second electrode,said second electrode having a hole therethrough adapted to receive saidionized particles and to become heated by the action of said are therebyto pro- References Cited in the file of this patent UNITED STATESPATENTS 948,372 Du Pont Feb. 8, 1910 2,215,155 Kallmann Sept. 17, 19402,743,366 Hershberger Apr. 24, 1956 2,765,975 Lindenblad Oct. 9, 19562,808,510 Norton Oct. 1, 1957 OTHER REFERENCES Lapp et a1.: NuclearRadiation Physics, Prentice-Hall, Inc. (1948), pages 127-128, 261-262,267-270, 274-275.

Oldenberg: Introduction to Atomic Physics, McGraw- 20 Hill Book Company,Inc. (1949), page 63.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent. N00 2360614 November 152 1960 George E. Mallinckrodt It is hereby certified thaterror appears in the printed specification of the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 4, line 67, after "therefrom" insert a comma Signed and sealedthis 25th day of April 1961 (SEAL) Atteat:

ERNEST Wo SWIDER DAVID L, LADD Attesting Oficer Commissioner of PatentsUNITED STATES PATENT OFFICE OERTIFECATE OF CORRECTION Tn In 1n 1 1Patent N0 2 960 614 lwvemuel 5 1963 George En Mallinekrodt It is herebycertified that error a of the above numbered patent requiring 0 Patentshould read as corrected below.

ppears in the printed specification orrection and that the said LettersColumn 4 line 67 after e]r1ere1.rom" insert a comma,

Signed and sealed this 25th day of April 1961a (SEAL) Attest: ERNEST W0SWIDER DAVID L, LADD Attesting ()ficer Commissioner of Patents

